Computer-aided design of air-gapped magnetic core inductors with minimum DC winding resistance

The method of computer-aided design of air-gapped inductors operating with de bias current is described. An algorithm for the minimum de resistance of the winding for a desired value of the inductance is given. Simultaneously, this permits us to determine the optimal length of the air gap, to choose a suitable operating point on the normal magnetization curve and to calculate the minimum number of turns of the winding under given inductor operation conditions, i.e., the ac voltage value across the inductor and its frequency, and the value of the de bias current superimposed in the same winding. The method presented here uses the normal magnetization curve of the core material and the family of relative incremental permeability curves of this material.